You have a healthy weight!
How BMI is Mathematically Calculated
Body Mass Index (BMI) represents a simple statistical index comparing an individual's mass directly against their height profile. The mathematical formulas are defined as follows:
Metric Formula
Imperial Formula
World Health Organization (WHO) BMI Classifications
Adult weight status classes are mapped internationally according to the following strict WHO ranges:
| BMI Range | Classification | Health Risk Category |
|---|---|---|
| < 18.5 | Underweight | Nutritional Deficiencies |
| 18.5 – 24.9 | Normal Weight | Minimal / Optimal Healthy State |
| 25.0 – 29.9 | Overweight | Increased cardiovascular risk |
| ≥ 30.0 | Obese | High hypertension and diabetic risks |
Frequently Asked Questions
While the mathematical BMI calculation is identical, weight classifications for children and adolescents (ages 2 to 19) are interpreted using percentile metrics relative to other children of the identical age and sex. This calculator screens for adult standards (ages 20+).
BMI does not measure body fat percentage directly. Consequently, high muscle volume can skew calculations upwards (misdiagnosing muscular individuals as overweight). Conversely, loss of muscle mass in elderly individuals may hide obesity ("normal-weight obesity").